An Extensive Analysis of Biodiesel Blend Combustion Characteristics under a Wide-Range of Thermal Conditions of a Cooperative Fuel Research Engine

Abstract

Examining the influence of thermal conditions in the engine cylinder at the start of fuel injection on engine combustion characteristics is critically important. This may help to understand physical and chemical processes occurring in engine cycles and this is relevant to both fossil fuels and alternative fuels like biodiesels. In this study, six different biodiesel–diesel blends (B0, B10, B20, B40, B60 and B100 representing 0, 10, 20, 40, 60 and 100% by volume of biodiesel in the diesel–biodiesel mixtures, respectively) have been successfully tested in a cooperative fuel research (CFR) engine operating under a wide range of thermal conditions at the start of fuel injection. This is a standard cetane testing CFR-F5 engine, a special tool for fuel research. In this study, it was further retrofitted to investigate combustion characteristics along with standard cetane measurements for those biodiesel blends. The novel biodiesel has been produced from residues taken from a palm cooking oil manufacturing process. It is found that the cetane number of B100 is almost 30% higher than that of B0 and this could be attributed to the oxygen content in the biofuel. Under similar thermal conditions at the start of injection, it is observed that the influence of engine load on premixed combustion is minimal. This could be attributable to the well-controlled intake air temperature in this special engine and therefore the evaporation and mixing rate prior to the start of combustion is similar under different loading conditions. Owing to higher cetane number (CN), B100 is more reactive and auto-ignites up to 3 degrees of crank angle (DCA) earlier compared to B0. It is generally observed in this study that B10 shows a higher maximum value of in-cylinder pressure compared to that of B0 and B20. This could be evidence for lubricant enhancement when operating the engine with low-blending ratio mixtures like B10 in this case.

Performance and Emission of Diesel Engine Fuelled by Commercial Bio-Diesel Fuels in Indonesia

“…However, it can be concluded that an increase of biodiesel percentage in blends decreases the calorific value of diesel fuel. Similar findings were observed by Nguyen et al (2020) who analysed the biodiesel (B0-B100) blend combustion characteristic under a wide range of thermal condition. The authors state that the high CN of B100 that has more percentage of blends is more reactive and auto-ignites rather than the biodiesel that has low percentage of blends.…”

A Study on Utilization of High-Ratio Biodiesel and Pure Biodiesel in Advanced Vehicle Technologies

“…A number of papers have studied the characteristics of emissions, performance and combustion of high-ratio biodiesel fuel and pure diesel fuel. The performance and emissions characteristics of biodiesel engines are mainly determined by engine type and its settings, engine emissions control technologies, testing methodology and biodiesel resources [1,[3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22]. However, there is a lack of studies investigating the impact of high-ratio biodiesel blends fuel and pure biodiesel (B100) on the performance and emissions of advanced vehicle technologies.…”

Investigation of the Impact Bioethanol Blends into Biodiesel on Combustion Characteristics, Engine Performance, and Emissions of Diesel Engine

“…As a result, the delay of ignition duration is reduced. In comparison, the combustion behavior is almost similar to the commercial diesel [4]. The shorter ignition delay from using biodiesel fuel leads to the combustion process starting to begin before the engine's optimization point, which is set up by the manufacturer for commercial diesel fuel.…”